Given the need to assess, decontaminate, and verify decontamination of a facility for reoccupation after possible chemical agent contamination, various techniques and instruments have been developed for use by the personnel who perform this hazardous work. When performing such tasks in a contaminated or potentially contaminated environment, specially trained workers must wear cumbersome personal protective equipment (PPE). The PPE typically includes a chemical agent resistant hooded garment with gloves, boots, and respirator equipment. Handheld chemical agent detectors, sampling kits, and decontamination kits are commercially available and used in these applications. However, the accuracy and reliability of such handheld chemical agent detectors are compromised to some extent in order to achieve the size restrictions needed for portability. Accordingly, it is standard practice to hand gather a larger number of samples for subsequent analysis. A large number of samples are gathered because the exact location of contamination is generally unknown. Follow-on analysis is then typically performed at a laboratory using stationary, but highly accurate and reliable analytical equipment. In addition to being inefficient from a labor perspective in both the collection and subsequent analysis time, this prior art technique places personnel at greater risk. This is due to the longer duration needed to collect numerous samples with little to no feedback on the precise location of the chemical agent contamination.
Mass spectrometry (MS) using direct analysis in real time (referred to under the trademark DART or DART-MS) ionization provides a preferred analytical means for subsequent laboratory analysis of the samples collected in the application described above. The DART coupled with an appropriate MS system provides highly accurate and reliable analytical results in this application. Detailed teachings to enable practice of DART-MS ionization systems are provided in U.S. Pat. No. 7,112,785 entitled “Method for Atmospheric Pressure Analyte Ionization” and U.S. Pat. No. 7,196,525 entitled “Sample Imaging,” both of which are incorporated herein by reference in their entirety.
When using a DART-MS system, such as the JEOL DART-AccuTOF described in the above-incorporated patents, it is generally a required element of the operation to bring the sample to be analyzed in close proximity to the ion source of the DART-MS where it is typically held by hand in such proximity until a reading on the DART-MS is obtained.
While some attempts have been made to provide a sample line for greater convenience and flexibility while using the DART-MS, these attempts have generally focused on moving the ion source to the sampling point and transporting the resulting ions through the sample line to the MS. The generation of ions and their subsequent transportation has been fraught with limitations because it is inherently difficult to move ionized species over the desired distances, such as 10 to 20 feet, at atmospheric pressure. Losses over even shorter distances such as 3 feet can occur through multiple pathways including gas and surface reactions as well as charge neutralization. Accordingly, handheld detectors for onsite analysis coupled with sampling kits for offsite laboratory analysis have proliferated in this application. In addition, many subject matter experts teach away from attempting to bring high value, sensitive instruments such as the DART-MS into potentially contaminated sites.
Accordingly, what is needed is a means to utilize the highly accurate and reliable DART-MS device to detect chemical agents at sample location points approximately 20 feet away from the device with the ability to easily move the sampling point to any desired point within the sampling range, thus allowing the operator to systematically scan a site in a fashion similar to that used with a handheld detector.